Multimorbidity Patterns and Obesity Among Americans Turning Forty

PurposeTo identify multimorbidity patterns among U.S adults entering their 40s.DesignCross-sectional analysis of cohort data.Setting and SampleData are from the National Longitudinal Study of Youth 1979, a nationally representative cohort born between 1957-1964 (n = 8104) who were followed from adolescence into adulthood; this analysis used data collected when participants entered their 40s (1998-2006).Measures and AnalysisParticipants self-reported whether they had ever been diagnosed with each of 7 chronic conditions: hypertension, diabetes, non-skin cancers, chronic lung disease, heart disease, mental disorders, and arthritis or rheumatism. We used latent class analysis to identify multimorbidity patterns. Multimorbidity was defined as ≥2 diagnosed conditions and obesity as body mass index ≥30 kg/m² from self-reported height and weight. We used multinomial survey-adjusted logistic regressions to examine associations between obesity and disease clusters.ResultsAt mean age of 41y, 10.8% of adults in the U.S. had multimorbidity; 26.3% had obesity. Three patterns emerged: healthy (≤1 disease), an arthritis-mental health conditions-dominated cluster (5.6%) and a hypertension-diabetes-dominated cluster (2.4%). People with obesity had 5 times higher odds of having a hypertension-diabetes-dominated cluster (OR = 5.2, 95%CI: 3.2-8.5) and double the odds of having an arthritis-mental health conditions-dominated cluster (1.7, 1.2-2.2) compared to normal-weight individuals.ConclusionAmong U.S. adults in their 40s, multimorbidity clusters were dominated by arthritis-mental health and hypertension-diabetes; both disproportionately affected individuals with obesity.